The transformation of forest into pastures in the Brazilian Amazon leads to significant consequences to climate at local scale. In the region of Alta Floresta (Mato Grosso, Brazil), deforestation has been intense with over half the forests being cut since 1970. This article first examines the evolution of precipitation observed in this region and shows a significant trend in the decrease in total precipitation especially at the end of the dry season and at the beginning of the rainy season. The study then compares the temperatures measured in cleared and forested sectors within a reserve in the area of Alta Floresta (Mato Grosso, Brazil) between 2006 and 2007. The cleared sector was always hotter and drier (from 5% to 10%) than the forested area. This difference was not only especially marked during the day when it reached on average 2A degrees C but also seemed to increase during the night with the onset of the dry season (+0.5A degrees C). The Urban Heat Island effect is also evident especially during the night and in the dry season.
- AMERICAN SECTOR
- FOREST DIEBACK
[Dubreuil, Vincent; Funatsu, Beatriz; Nedelec, Vincent] Univ Rennes 2, Lab COSTEL, CNRS, LETG UMR6554, F-35043 Rennes, France; [Debortoli, Nathan] Univ Brasilia, Ctr Sustainable Dev, BR-70904970 Brasilia, DF, Brazil; [Durieux, Laurent] Inst Rech Dev Representat IRD Bresil, Unite Espace S140, BR-71619971 Brasilia, DF, Brazil
Dubreuil, V (reprint author), Univ Rennes 2, Lab COSTEL, CNRS, LETG UMR6554, Pl Recteur Henri le Moal, F-35043 Rennes, France.